1. Field of the Invention
The present invention relates to an image transfer apparatus and, more particularly, to an image transfer apparatus with a streak removal system.
2. Description of Related Developments
Image scanners capture images using sensors such as gray scale sensors or red(R), green(G), and blue(B). For a typical desktop scanner, these sensors could be a single or three row CCD. The sheet medium or image is moved relative to the sensors or the sensors relative to the image in a scanning or process direction while data is being sampled from the sensors. The captured data is recombined digitally to form a full two dimensional image which may be stored, digitally manipulated and/or output to a printer for example. A problem arises when dirt streaks corrupt the image. An example of such a problem is when dirt in the scan path caught between the paper and the scan bar creates thin vertical lines that appear on the scanned image. A further example of such a problem is when dirt in images transfer path is caught between the paper and another surface and creates thin vertical lines that appear on the scanned image. To remove the defect, complex approaches have been employed such as the addition of sensors in the scan head or complex image processing to attempt to detect and remove the streak. Such solutions can be expensive or unreliable and difficult to implement where the image processing algorithm is attempting to distinguish between the streaks and vertical lines that are properly in the scanned image leading to false detection and complex algorithms for avoidance. Accordingly, there is a desire to provide a streak detection and elimination system that is inexpensive, simple and robust.